# By what factor should the length of a simple pendulum be changed in order to triple the period of vibration?

Jan 13, 2018

9 times of the previous length

#### Explanation:

Relation between time period T and length l of pendulum is given as T $\propto$ √l
So, we can write,
$\frac{T 2}{T 1}$ = √(l2)/(l1)  (where T1 and T2 are initial and final time period and L1 and L2 are initial and final length of the pendulum respectively as required)
Given, T2 = 3 T1
So, $\frac{l 2}{l 1}$ will be 9
Hence length should be made 9 times than that of the previous value.